This invention refers to a method and a device for plasma cutting of non-metallic materials, which can be applied in industrial construction when cutting items such as concrete slabs or panels.
A method is known for the cutting of non-metallic materials, whereby the processed material is subjected to the mechanical action of a diamond disc which rotates and moves to cut. The main disadvantage of this known method is that, the diamond disc is very expensive and wears out relatively easily.
A method for plasma cutting and processing of non-metallic materials is also known, whereby the plasma arc, generated by a plasmatron, burns between an electrode-cathode and a nozzle-anode, and is blown by the plasma-forming gas, which is fed under pressure to the chamber of the plasmatron. As a result, in the nozzle channel a narrow plasma arc and a plasma torch are formed, the latter flowing out of the nozzle. The material, which is processed, is subjected to the action of the plasma torch, and as a result the cut is formed.
Several disadvantages of the latter method are that the cutting is done by an indirect arc, which significantly reduces the efficiency of the process, the zone affected by the heat is wide, and cracks can be formed in the material.
A common disadvantage of the known methods for cutting non-metallic materials is the low cutting speed, which makes for a reduced productivity.
A device for plasma cutting of non-metallic materials is known, which consists of a plasmatron, affixed on a bearing strip, mounted on a tractor, which moves. The plasmatron consists of a central electrode-cathode, on which an insulator is mounted, while on the latter the base-frame is mounted, which has a nozzle at the front end. Three orifices are disposed in the base-frame, respectively, for feeding plasma forming gas, cooling water and current supply.
A disadvantage of this known device is that, it does not allow for direct interaction of the plasma arc, obtained in the plasmatron, its cutting, high-temperature plasma column and the non-metallic material being cut, as occurs when cutting metals.